What Are Our Concerns About Bearings（30）

Q1: Type 30000 and type 70000 bearings are often used in pairs. At this time, what is positive installation?  What is anti-installation?  What is “face to face” installation?  What do you mean “back on”？

When used in pairs, the “face to face” installation mode is called forward installation, and the “back to back” installation mode is called reverse installation.  And “face to face” refers to the narrow edge of the two bearing outer rings, and “back to back” refers to the wide edge of the two bearing outer rings.  

Q2: What is the difference between tapered roller bearing and thrust roller bearing?

Tapered roller bearings mainly bear combined radial and axial loads.  Bearing capacity depends on the raceway Angle of the outer ring, and the greater the Angle, the greater the bearing capacity.  This kind of bearing belongs to the separation type bearing, which is divided into single row, double row and four row tapered roller bearings according to the number of rolling columns in the bearing.  

Thrust roller bearings are used to bear combined axial and radial loads mainly in axial direction, but the radial load shall not exceed 55% of the axial load.  Compared with other thrust roller bearings, this kind of bearing has lower friction coefficient, higher speed and self-aligning performance.  

Q3: According to the direction of the load it can bear, which kinds of rolling bearings?

According to the direction of load bearing, bearings are divided into：  

Radial bearing: mainly bearing radial load.  Such as: self-aligning ball bearings, self-aligning roller bearings, deep groove ball bearings  

Thrust bearing: can only withstand axial load.  Such as: thrust ball bearings, two-way thrust ball bearings  

Centripetal thrust bearing: bearing radial and axial loads simultaneously.  Such as: angular contact ball bearings, thrust self-aligning roller bearings, tapered roller bearings.  

Q4: How to judge the authenticity of SKF?

• 1. The packaging of genuine imported SKF bearings, small models are every 10 or every 5 plastic small packaging, plastic plastic cloth, plastic cloth material is flexible.  Fake plastic packaging cloth is brittle and hard.  
• 2. The packaging box of genuine imported SKF bearings is printed with exquisite printing. The back of the packaging box is an anti-counterfeiting bar code, and the side is the model and the production country.  Fakes are generally printed directly, so you can see the printing process.  
• 3. There are many countries of production on the sides of packaging boxes. In the domestic market, Paraguay, Malaysia, China, Italy and France are more common, which is the different division of labor of SKF factories around.  Most of the countries where fakes are produced are MADE IN France  
• 4, on the other side of the box there is A 5 mm dark color watermark small box, there is A small A in the upper left corner, the watermarking process.  The fake dark color can only be printed in light blue.  
• 5, the side of the packaging box adopts the glue with strong viscosity, which is difficult to open.  Fake boxes are sealed with common glue or plastic welding rods, which are easier to open.  
• 6. The bearing in the box is sealed with plastic seal. After opening, there is little anti-rust oil of genuine goods.  
• 7. The chamfering of the bearing (the junction of the vertical intersection of two surfaces) is quite smooth, blackened and metallic.  Fake chamfering is either not black, or laser is used to brush burning black, not metallic luster, hard rubbing can fade color.  

Q5: Can the bearing of bucket lift machine use SKF bearing and FAG bearing at the same time?  

It can be used. In fact, FAG and SKF have the same quality. It’s just a brand problem. 

Q6: What is 22318CAK/C4W33 bearing clearance ?

This is for self-aligning roller bearings  

C4 oil gap, is a large oil gap, generally used in mining equipment  

22318CAK/C4W33 bearing clearance is 160.  

Q7: What is the use of deep groove ball bearings?

The inner and outer raceways of deep groove ball bearings are arc-shaped deep grooves, and the radius of the groove is slightly larger than the radius of the ball.  Mainly used for bearing radial load, also can bear certain axial load.  When the radial clearance of the bearing increases, it has the function of angular contact ball bearing, which can bear larger axial load and is suitable for high-speed rotation.  Bearing can still work normally when shell hole and shaft tilt 8 ‘~ 16’, but its service life is affected.  When the speed is high and the thrust ball bearing is not suitable, this kind of bearing can bear pure axial load.  

Deep groove ball bearings generally use a two-part composite steel plate stamping cage, but large size or high-speed bearings use solid cage, this cage is the same as stamping cage by the ball, high-speed deep groove ball bearings usually by the inner ring or outer ring rim.  

Compared with other types of bearings with the same size, deep groove ball bearings have small friction coefficient, lower vibration and noise, high limit speed and high precision, so they are the preferred bearing types for users when selecting bearings.  However, this kind of bearing is not resistant to impact and is not adapted to bear heavy loads.  

Deep groove ball bearings are simple in structure and convenient in use. They are a kind of bearings with large production volume and wide application range.  Widely used in automobiles, household appliances, machine tools, motors, water pumps, agricultural machinery, textile machinery and many other fields.  Its output accounts for more than 70% of the total output of bearings. It is a kind of bearings with high output, common use and cheap price in China.  

Q8: What series of deep groove ball bearings are commonly used, what do they mean respectively?  

• 1. Single row deep groove ball bearings  
• 2, single row deep groove ball bearings with dust cover  
• 3. Single row deep groove ball bearing with dust cover and sealing ring  
• 4. Single row deep groove ball bearings with stop groove and stop ring on the outer ring  
• 5. Deep groove ball bearing with ball gap  
• 6. Double row deep groove ball bearings  

According to the size of deep groove ball bearings, they can be divided into:  

• (1) miniature bearings —- nominal outer diameter size range of bearings below 26mm;  
• (2) small bearing —- nominal outer diameter size range of 28-55mm bearing;  
• (3) small and medium-sized bearings —- nominal outer diameter size range of 60-115mm bearings;  
• (4) medium and large bearings —- bearing with nominal outer diameter size range of 120-190mm  
• (5) large bearing —- nominal outer diameter size range of 200-430mm bearing;  
• (6) Super large bearings —- bearing with nominal outer diameter size range of more than 440mm.